'use strict';

// Do this as the first thing so that any code reading it knows the right env.
process.env.BABEL_ENV = 'development';
process.env.NODE_ENV = 'development';

// Makes the script crash on unhandled rejections instead of silently
// ignoring them. In the future, promise rejections that are not handled will
// terminate the Node.js process with a non-zero exit code.
process.on('unhandledRejection', err => {
   throw err;
});

// Ensure environment variables are read.
require('../config/env');

const fs = require('fs');
const chalk = require('react-dev-utils/chalk');
const webpack = require('webpack');
const WebpackDevServer = require('webpack-dev-server');
const clearConsole = require('react-dev-utils/clearConsole');
const checkRequiredFiles = require('react-dev-utils/checkRequiredFiles');
const {
   choosePort,
   createCompiler,
   prepareProxy,
   prepareUrls,
} = require('react-dev-utils/WebpackDevServerUtils');
const openBrowser = require('react-dev-utils/openBrowser');
const semver = require('semver');
const paths = require('../config/paths');
const configFactory = require('../config/webpack.config');
const createDevServerConfig = require('../config/webpackDevServer.config');
const getClientEnvironment = require('../config/env');
const react = require(require.resolve('react', { paths: [paths.appPath] }));

const env = getClientEnvironment(paths.publicUrlOrPath.slice(0, -1));
const useYarn = fs.existsSync(paths.yarnLockFile);
const isInteractive = process.stdout.isTTY;

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
   process.exit(1);
}

// Tools like Cloud9 rely on this.
const DEFAULT_PORT = parseInt(process.env.PORT, 10) || 3000;
const HOST = process.env.HOST || '0.0.0.0';

if (process.env.HOST) {
   console.log(
      chalk.cyan(
         `Attempting to bind to HOST environment variable: ${chalk.yellow(
            chalk.bold(process.env.HOST)
         )}`
      )
   );
   console.log(
      `If this was unintentional, check that you haven't mistakenly set it in your shell.`
   );
   console.log(
      `Learn more here: ${chalk.yellow('https://cra.link/advanced-config')}`
   );
   console.log();
}

// We require that you explicitly set browsers and do not fall back to
// browserslist defaults.
const { checkBrowsers } = require('react-dev-utils/browsersHelper');
checkBrowsers(paths.appPath, isInteractive)
   .then(() => {
      // We attempt to use the default port but if it is busy, we offer the user to
      // run on a different port. `choosePort()` Promise resolves to the next free port.
      return choosePort(HOST, DEFAULT_PORT);
   })
   .then(port => {
      if (port == null) {
         // We have not found a port.
         return;
      }

      const config = configFactory('development');
      const protocol = process.env.HTTPS === 'true' ? 'https' : 'http';
      const appName = require(paths.appPackageJson).name;

      const useTypeScript = fs.existsSync(paths.appTsConfig);
      const urls = prepareUrls(
         protocol,
         HOST,
         port,
         paths.publicUrlOrPath.slice(0, -1)
      );
      // Create a webpack compiler that is configured with custom messages.
      const compiler = createCompiler({
         appName,
         config,
         urls,
         useYarn,
         useTypeScript,
         webpack,
      });
      // Load proxy config
      const proxySetting = require(paths.appPackageJson).proxy;
      const proxyConfig = prepareProxy(
         proxySetting,
         paths.appPublic,
         paths.publicUrlOrPath
      );
      // Serve webpack assets generated by the compiler over a web server.
      const serverConfig = {
         ...createDevServerConfig(proxyConfig, urls.lanUrlForConfig),
         host: HOST,
         port,
      };
      const devServer = new WebpackDevServer(serverConfig, compiler);
      // Launch WebpackDevServer.
      devServer.startCallback(() => {
         if (isInteractive) {
            clearConsole();
         }

         if (env.raw.FAST_REFRESH && semver.lt(react.version, '16.10.0')) {
            console.log(
               chalk.yellow(
                  `Fast Refresh requires React 16.10 or higher. You are using React ${react.version}.`
               )
            );
         }

         console.log(chalk.cyan('Starting the development server...\n'));
         openBrowser(urls.localUrlForBrowser);
      });

      ['SIGINT', 'SIGTERM'].forEach(function (sig) {
         process.on(sig, function () {
            devServer.close();
            process.exit();
         });
      });

      if (process.env.CI !== 'true') {
         // Gracefully exit when stdin ends
         process.stdin.on('end', function () {
            devServer.close();
            process.exit();
         });
      }
   })
   .catch(err => {
      if (err && err.message) {
         console.log(err.message);
      }
      process.exit(1);
   });
